The present invention relates to energy generation systems and more particularly to co-production of hydrogen and electrical energy.
In recent years, various attempts have been made to use a combined cycle power generating system, in which system a fuel is burned in a combustor to produce a hot gas which hot gas drives a gas turbine to generate electrical power. The combustor in a combined cycle power generation system is typically cooled by compressed air, which compressed air is readily available in the plant. Using compressed air for cooling the combustor limits the lower limit of the flame temperature in the combustor, which in turn, may result in higher nitrous-oxide (NOx) production and emission.
A co-production route typically produces electricity as well as some liquid fuel or chemical from the same feedstock. The concept of co-production is based on producing chemicals or liquid fuels during the lean electricity demand period and using them to augment power production during the peak period. Hydrogen, one of the most extensively used fuels, that is produced in such a co-production plant can be used in several ways including electricity generation.
Typically Steam reforming of a hydrocarbon fuel, such as natural gas, is the primary means of hydrogen production. The reforming reaction is an endothermic reaction wherein external heat has to be supplied. Typically this external heat is supplied by burning a part of the fuel used for reforming or any fuel rich gas available in the reforming plant. This process is energy intensive and may produce significant amount of nitrous oxides (NOx).
With the advent of hydrogen economy the demand for a co-production system, which system can produce hydrogen and electricity, is expected to increase. Accordingly, there is a need to design a co-production system, which system can produce hydrogen and electrical energy in an efficient manner while limiting the NOx emission.